Nappanee, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.9 °C (low) to 15.2 °C (high). Annual precipitation averages 998.7 Millimeters. Nappanee is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8 °C | -0.2 °C | 65.02 mm |
| February | -6.8 °C | 1.9 °C | 56.13 mm |
| March | -2.1 °C | 8.2 °C | 58.93 mm |
| April | 3.7 °C | 15.3 °C | 90.68 mm |
| May | 10.1 °C | 21.4 °C | 111 mm |
| June | 15.3 °C | 26.6 °C | 104.65 mm |
| July | 17.2 °C | 28.3 °C | 109.47 mm |
| August | 16.2 °C | 27.3 °C | 103.89 mm |
| September | 12 °C | 24.1 °C | 81.28 mm |
| October | 5.9 °C | 17.1 °C | 83.57 mm |
| November | 0.3 °C | 9.2 °C | 73.15 mm |
| December | -4.8 °C | 2.6 °C | 60.96 mm |
| Annual | 4.9 °C | 15.2 °C | 998.73 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |